Double pass process of making a self adhering roofing membrane with improved adhesion at lower installation temperature

ABSTRACT

A self-adhering roofing membrane may include a polymeric membrane. The roofing membrane may include a first adhesive layer disposed on a major surface of the polymeric membrane. The first adhesive layer may include one or both of a hot melt adhesive and a butyl rubber-based adhesive. The roofing membrane may include a UV curable adhesive layer disposed on the first adhesive layer. The UV curable adhesive layer may have a thickness of less than about 4 mils.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Division of pending U.S. application Ser. No.17/324,232 filed May 19, 2021. The entire contents of theabove-identified application are incorporated by reference for allpurposes.

BACKGROUND

Conventional roofing membranes are often applied to roofing boardsand/or other surfaces using adhesives, which may prevent the need to useany fasteners that would need to puncture the roofing membrane and whichcould lead to water ingress. However, while the adhesives used onconventional roofing membranes are often adequate to secure the roofingmembrane to the roof, such adhesives typically have a small workabletemperature range at which the adhesives remain tacky. In particular,conventional adhesives lose their tackiness at lower temperatures, whichmay limit the effectiveness of the roofing membrane and/or limit theinstallation of the roofing membranes to times when certainenvironmental conditions are present. Additionally, conventionaladhesives tend to have low peel strengths and may exhibit cohesivefailures over time. Therefore, improvements in roofing membranes aredesired.

SUMMARY

In one embodiment, a self-adhering roofing membrane may include apolymeric membrane is provided. The roofing membrane may include a firstadhesive layer disposed on a major surface of the polymeric membrane.The first adhesive layer may include one or both of a hot melt adhesiveand a butyl rubber-based adhesive. The roofing membrane may include a UVcurable adhesive layer disposed on the first adhesive layer. The UVcurable adhesive layer may have a thickness of less than about 4 mils.

In some embodiments, a glass transition temperature of the UV curableadhesive may be less than about −20° C. The UV curable adhesive mayexhibit a peel strength of at least 5 pounds per linear inch. Athickness of the first adhesive layer is between about 2 mils and 15mils. The polymeric membrane may include one or more selected from agroup comprising polyvinyl chloride (PVC), thermoplastic polyolefin(TPO), and ethylene propylene diene monomer (EPDM). The roofing membranemay include a release liner coupled with the UV curable adhesive layer.The release liner may include a UV blocking material.

In another embodiment, a self-adhering roofing membrane may include apolymeric membrane. The roofing membrane may include a first adhesivelayer disposed on a major surface of the polymeric membrane. The roofingmembrane may include a UV curable adhesive layer disposed on the firstadhesive layer. The UV curable adhesive layer may have a thickness ofless than about 4 mils.

In some embodiments, the UV curable adhesive layer may be only partiallycured prior to installation. The UV curable adhesive may include betweenabout 20% and 40% of a tackier resin, between about 0% and 15% of aninitiator, and between about 45% and 80% of an acrylic resin. Theself-adhering roofing membrane may remain tacky at temperatures as lowas about 15° F. The first adhesive layer may include an additional UVcurable adhesive. The polymeric membrane may be a single ply membrane.

In one embodiment, a method of manufacturing a self-adhering roofingmembrane is provided. The method may include applying a first adhesivelayer to a major surface of a polymeric roofing membrane. The method mayinclude at least partially curing the first adhesive layer. The methodmay include applying a UV curable adhesive layer atop the at leastpartially cured first adhesive layer. The method may include exposingthe UV curable adhesive to a UV light source to at least partially curethe UV curable adhesive layer. The method may include compressing thepolymeric roofing membrane, the first adhesive layer, and the UV curableadhesive layer to form a self-adhering roofing membrane. Aftercompression the UV curable adhesive layer may have a thickness of lessthan about 4 mils.

In some embodiments, applying the UV curable adhesive may include one ormore selected from a group comprising roll coating, transfer coating,extruding, spray coating, and die coating. Exposing the UV curableadhesive to the UV light source may include exposing the UV curableadhesive to between about 100 millijoules of energy per cm² and 300millijoules of energy per cm². The light source may include a lightsource that emits light in one or more selected from a group comprisinga UVA wavelength, a UVB wavelength, and a UVC wavelength. The lightsource may include natural light. The at least partially cured firstadhesive layer may be at a lower temperature than the UV curableadhesive layer during application of the UV curable adhesive layer. Themethod may include applying a release liner to the UV curable adhesivelayer before or during compression of the polymeric roofing membrane,the first adhesive layer, and the UV curable adhesive layer.

BRIEF DESCRIPTION OF THE DRAWINGS

A further understanding of the nature and advantages of variousembodiments may be realized by reference to the following figures. Inthe appended figures, similar components or features may have the samereference label. Further, various components of the same type may bedistinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If only the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label.

FIGS. 1A and 1B illustrate an embodiment of a roofing membrane accordingto embodiments of the present invention.

FIG. 2 illustrates a process of manufacturing a roofing membraneaccording to embodiments of the invention.

DETAILED DESCRIPTION

The subject matter of embodiments of the present invention is describedhere with specificity to meet statutory requirements, but thisdescription is not necessarily intended to limit the scope of theclaims. The claimed subject matter may be embodied in other ways, mayinclude different elements or steps, and may be used in conjunction withother existing or future technologies. This description should not beinterpreted as implying any particular order or arrangement among orbetween various steps or elements except when the order of individualsteps or arrangement of elements is explicitly described.

Embodiments of the present invention are directed to roofing membranesthat include adhesives that enable the roofing member to remain tackyfor application to roofing boards and other surfaces at lowertemperatures. In particular, embodiments may include roofing membranesthat remain tacky at temperatures as low as 15° F. Embodiments mayinclude an adhesive composition that includes at least two layers ofadhesive applied to a surface of the roofing membrane, with an outeradhesive layer including a UV curable adhesive that remains tacky at lowtemperatures. The UV curable adhesive may be applied at a low thickness,which may allow UV light to penetrate into a greater percentage of theUV curable adhesive. By using two, separately applied adhesive layersthat include a thin UV curable adhesive, a high cross-linking density ofbetween about 60% and 90% may be achieved. The adhesives used in theroofing membranes of the present invention may be fully cured duringmanufacturing and/or may be partially cured during manufacturing suchthat the adhesive may fully cure during and/or after installation of theroofing membrane. The roofing membranes of the present invention mayutilize adhesives that provide high peel strengths (between five and 10pounds per linear inch (PLI) or more) when used on conventional roofingsubstrate materials, such as ISO (paper and/or glass-facedpolyisocyanurate boards), oriented strand board (OSB) boards, gypsumboards (which may be standard and/or faced with fiberglass), and/orother conventional roofing materials.

Turning now to FIGS. 1A and 1B, one embodiment of a roofing membrane 100is illustrated. Roofing membrane 100 may be positioned atop roofstructure, oftentimes above an insulation layer, and may be configuredto prevent leaks in the roofing structure and/or to provide aestheticappeal. Typically, the roofing membrane 100 may be in the form of asingle ply membrane. The term “single-ply” may be used to describe aroof structure having a single application of a roofing membrane 100,but the roofing membrane 100 itself may include multiple layers. Forexample, the roofing membrane 100 may include polymer layers,reinforcing layers, adhesive layers, coatings, a fleece layer, and thelike. It will be appreciated that in some embodiments, multiple layersof roofing membrane 100 may be applied to a single roof structure.

Oftentimes, the roofing membrane 100 may be provided as a roll of flat,flexible membrane that may be rolled out on top of the roof structure.For example, a single ply roofing membrane 100 may be supplied in anyworkable size (such as, but not limited to, rolls of 10 feet wide ormore and containing 100 linear feet or more of roofing membrane 100).Oftentimes, the roof structure may be too large to be covered by asingle piece of roofing membrane 100. In such instances, multiple piecesof roofing membrane 100 may be overlapped and joined at the seams usinga waterproof joining method. For example, seams of adjacent pieces ofroofing membrane 100 may be joined by priming and/or preparing edges ofthe roofing membranes 100 and then applying a tape to the primed and/orprepared edges, using heat welding and/or using another form of adhesivebonding. In priming or preparing the edges, the installer must wait forthe primer material to flash before applying the adhesive. Improperapplication of the primer and/or adhesive may result in an improperbond, which may create immediate and/or long term roofing problems, suchas leakage. Examples of using and installing single ply roofingmembranes 100 may be found in U.S. Patent Publication No. 2016/0362894,entitled “Sheet Roofing with Pre-Taped Seams and Tape Therefor” andfiled Aug. 25, 2016, the entire contents of which is hereby incorporatedby reference for all purposes.

In some embodiments, roofing membrane 100 may include a polymericmembrane 102 and/or other waterproofing layer. The polymeric membrane102 may form the outer layer of the roof once fully installed and helpsprevent leaks in the roofing structure and provides aesthetic appeal tothe finished roof. For example, the waterproofing layer often provides auniform outer surface that provides an aesthetically pleasing finishedappearance to the roof. Polymeric membrane 102 may have a whiteexterior, but may be made in various other colors or shades, such asgrey, tan, black, and the like. White polymeric membranes 102 are oftenused to provide a pleasing appeal to the building and/or to reflectradiation and thereby minimize heat island effects. In otherembodiments, a black or other dark polymeric membrane 102 may beprovided. Such polymeric membranes 102 absorb more radiant heat thanwhite polymeric membranes 102. Additionally, in the winter, condensationevaporates quicker and snow and ice melt more rapidly on black roofsthan white roofs.

In some embodiments, polymeric membranes 102 may be formed of varioussynthetic rubber materials, modified bitumen, or thermoplasticmaterials. For example, roofing membrane 100 may commonly includethermoplastic polyolefin (TPO), polyvinyl chloride (PVC), ethylenepropylene diene monomer (EPDM), chlorinated polyethylene (CPA), and/ormodified bitumen, although some embodiments may use other thermosetand/or thermoplastic roofing membranes. In some embodiments, thepolymeric membrane 102 may include one or more polymers blended with oneor more fillers. For example, in some embodiments the polymericmembranes 102 may include some combination of the following materials:polypropylene, polyethylene, block copolymer polypropylene, rubber,plasticizers, fiberglass, carbon fiber, fire retardants, and the like.In another embodiment, a polymeric membranes 102 may have a more purepolymer blend without or with very few fillers. For example, thepolymeric membrane 102 may include mainly polypropylene or polyethyleneor some combination of these polymers with little to no fillers,although in some embodiments, these polymeric membranes 102 may includesome amount of a filler, such as a fire retardant. In some embodiments,the polymeric membrane may have a thickness of between about 500 μm toabout 3 mm, however other thicknesses are possible in variousembodiments.

When installing the roofing membrane 100, workers must often lay out orotherwise arrange multiple flat sheets of roofing membrane 100 to theroof structure. The sheets of roofing membrane 100 are then secured tothe roof structure, such as ballasting, mechanically fastening, adhesivebonding, induction welding, and/or heat welding the pieces of roofingmembrane 100 to the roof structure 100. Then the workers must seal anyseams formed between adjacent sheets of roofing membrane 100, such as byoverlapping the adjacent edges and joining the edges at the seams usinga waterproof joining method, such as using heat welding, using primerand tape, and/or other adhesive joining techniques. Additionally,workers must often install and connect electrical and/or mechanicalequipment on the roof prior to the completion of the roof installation.

In some embodiments, the roofing membrane 100 may include additionallayers, such as temporary protective layers that may be removed afterinstallation of the roofing membrane 100, one or more reinforcementlayers (such as scrim layers), base layers (such as fleece layers),and/or other layers.

Roofing membrane 100 may include multiple adhesive layers. For example,roofing membrane 100 may include a first adhesive layer 104 that ispositioned proximate a major surface of the polymeric membrane 102 and asecond adhesive layer 106 positioned atop the first adhesive layer 104.The first adhesive layer 104 may provide improved adhesion with thepolymeric layer 102, and may also provide tackiness at highertemperatures (which may exceed 160° F. in some cases), while the secondadhesive layer 106 may provide better peel strength and adhesion toroofing substrates (such as ISO, OSB, and/or gypsum roofing boards) andmay remain tacky at temperatures as low as 15° F. In combination, thefirst adhesive layer 104 and second adhesive layer 106 may provide aroofing membrane 100 with strong adhesion to roofing substrates acrosstemperature ranges that encompass both high and low environmentaltemperatures.

In some embodiments, the first adhesive layer 104 may include a hot meltadhesive, water-based adhesive, and/or butyl rubber-based adhesive. Thefirst adhesive layer 104 may be applied at a thickness of between about2 mils and 15 mils, between about 3 mils and 12 mils, between about 4mils and 10 mils, or between about 5 mils and 8 mils. The first adhesivelayer 104 may include between about 60% and 95% of a 100% cured acrylichigh molecular weight hot melt adhesive with 0 to 20% rosin or terpeneresin tackifier. The molecular weight of the resin may range be betweenabout 100,000 MV/g/mol and 600,000 MV/g/mol. Examples of acrylic resinsthat may be used include Acrynax 11588 and/or Acrynax 11891 fromFranklin Adhesives and Polymers. Additional examples of suitable acrylicresins may include Vinnapas UW 25FS and/or Vinnapas B/500/40 VL fromWacker Chemie AG. Suitable tackifiers may include Dymerex or Foral AX-Efrom Eastman Rosin Products.

The second adhesive layer 106 may be a UV curable adhesive, such as a UVcurable acrylic adhesive. The UV curable adhesive may fully cured duringmanufacturing and/or may be partially cured. In embodiments in which theUV curable adhesive is only partially cured, the UV curable adhesive maybe fully cured after installation by exposing the roofing membrane 100to a UV light source, such as a UV lamp and/or natural UV light(sunlight). The UV curable adhesive may have a thickness of less thanabout 4 mils, less than about 3.5 mils, less than about 3 mils, lessthan about 2.5 mils, less than about 2 mils, less than about 1.5 mils,less than about 1 mil, or less. The thickness of the UV curable adhesivemay be particularly important when the UV curable adhesive is onlypartially cured during manufacture, as UV energy may only penetrate 1 to2 mils into the UV curable adhesive. Thus, thinner UV curable adhesivelayers may have better cross-linking density than thicker layers.

The UV curable adhesive may include between about may include betweenabout 45% and 80% of a UV cross-linkable acrylic resin, between about20% and 40% of a tackifier resin, and between about 0% and 15% of aphoto-initiator and/or polymerizer. The high level of tackifier withinthe UV curable adhesive may increase the peel strength of the roofingmembrane 100. Non-limiting examples of UV cross-linkable acrylic resinsthat may be used include acResin® A260 and acResin® A250 produced byBASF. Non-limiting examples of tackifier resins that may be used includeKraton SYLVALITE RE 80HP Rosin Ester. Non-limiting examples ofphoto-initiators and/or polymerizers that may be used includebenzophenone and bismaleimides.

The UV curable adhesive may have a glass transition temperature that isless than about less than about −20° C., less than about −25° C., lessthan about −30° C., or less. The low glass transition temperatureenables the UV curable adhesive and roofing membrane 100 to remain tackyat low temperatures, such as temperatures as low as 15° F. The UVcurable adhesive may exhibits a peel strength of at least 5 pounds perlinear inch (PLI) when applied to conventional roofing materials, suchas ISO, OSB, and gypsum roofing boards. For example, the peel strengthof the UV curable adhesive may be between about 5 PLI and 15 PLI,between about 6 PLI and 12 PLI, between about 7 PLI and 9 PLI. Higherpeel strengths may be achieved in some embodiments.

In some embodiments, the roofing membrane 100 may include a releaseliner 108 that may be provided on an external surface of the roofingmembrane 100. For example, the release liner 108 may be coupled with anexposed surface of the second adhesive layer 106 to protect theadhesives of the roofing membrane 100 and to prevent the roofingmembrane 100 from adhering to any surfaces prior to removal of therelease liner 108 during the installation process. In some embodiments,the release liner may include a UV blocking material, such as Mylarand/or silicone-based release liners that include UV-absorbingchemicals. One example of a suitable release liner is Saint GobainNORFILM. This may be particularly useful in embodiments in which the UVcurable adhesive is only partially cured during the manufacturingprocess, as the UV blocking material may prevent the UV curable adhesivefrom fully curing during storage and ensures that the full cure occursonly after the release liner 108 has been removed during and/or afterthe installation process.

In some embodiments, the first adhesive layer 104 may include a UVcurable adhesive. In such embodiments, the UV curable adhesives used inthe first adhesive layer 104 and the second UV adhesive layer 106 may bethe same or different. In such embodiments, the first adhesive layer 104may have a thickness of less than about 4 mils, less than about 3.5mils, less than about 3 mils, less than about 2.5 mils, less than about2 mils, less than about 1.5 mils, less than about 1 mil, or less.

FIG. 2 illustrates one process of manufacturing a roofing membrane 200.The roofing membrane 200 may be similar to any of the roofing membrane100 described above. As illustrated, a polymeric layer 202 may beprovided. The polymeric layer 202 may be similar to those describedelsewhere herein, and may be passed under one or more adhesiveapplicators 210. Adhesive applicators 210 apply a first adhesivematerial 204, which may be similar to the first adhesive layer 104described elsewhere herein, to a major surface of the polymeric membrane202. The first adhesive material 204 may be applied by the adhesiveapplicators 210 using transfer coating, die coating, spray coating, rollcoating, and/or using other techniques to apply the first adhesivematerial 204 to a major surface of the polymeric membrane 202. The firstadhesive material 204 may be applied at a thickness of between about 2mils and 20 mils if water-based, butyl rubber-based, and/or a hot meltadhesive, and may be applied at a thickness of less than about 8 milsfor a UV curable adhesive. In some embodiments, the first adhesivematerial 204 may be applied using a single pass, while in otherembodiments multiple passes may be used to apply the first adhesivematerial 204 to a desired thickness. Pressure may be applied to thefirst adhesive material 204 and polymeric membrane 202 to help bond thetwo materials. Once applied, the first adhesive material 204 may bepartially or fully cured. The curing may be active or passive. Forexample, in some embodiments, the first adhesive material 204 (andpolymeric membrane 202) may be passed through and/or under an infrared(IR) heater, oven, microwave, and/or other heating source to dry and/orcure the first adhesive material. In some embodiments, the firstadhesive material 204 may be chemically cured and/or dried. In someembodiments, the first adhesive material 204 may be dried and/or curedby exposure to air, such as by passive exposure to air and/orcirculating air from a fan and/or other airflow device. In otherembodiments, additional drying and/or curing steps may be provided. Insome embodiments, prior to the application of the first adhesivematerial 204, a corona treatment may be applied to the polymericmembrane 202, following standard procedures known to the trade, toincrease surface energy and improve wettability of the adhesive layers.

After curing the first adhesive material 204, a second adhesive material206 that may include a UV curable adhesive (similar to second adhesivelayer 106) may be applied using one or more additional adhesiveapplicators 212. For example, the second adhesive material 206 may beroll coated, spray coated, extruded, transfer coated, and/or die coatedusing the adhesive applicators 212. The second adhesive material 206 maybe applied in one or more passes to a thickness of less than about 8mils, less than about 7 mils, less than about 6 mils, less than about 5mils, less than about 4 mils, less than about 3 mils, less than about 2mils, or less. After application, the second adhesive material 206 maybe at least partially cured. For example, the second adhesive material206 (and polymeric membrane 202 and first adhesive layer 204) may beexposed to one or more UV light sources 214 and/or heat sources 216 topartially and/or fully cure the second adhesive material 206. Forexample, the UV light source 214 may include a UV lamp that emits lightin the UVA, UVB, UVC, and/or UV visible light. In some embodiments, thelight source 214 may include natural light (with or without anartificial light source). The light source 214 may apply between about100 mj/cm² and 300 100 mj/cm² of energy to the second adhesive material206 to cure or partially cure the second adhesive material 206. Thesecond adhesive material 206 may be passed under the light source 216for between about 10 seconds and 120 seconds, between about 20 secondsand 90 seconds, or between about 30 seconds and 60 seconds. The heatsource 216 may include an IR heat source, an oven, microwave, and/orother heating element. The heat source 216 may expose the secondadhesive material 206 to temperatures of between about 100° F. and 300°F.

The roofing membrane 200 may be fed into one or more rollers 218, whichmay apply pressure to compress the roofing membrane 200 to a finalthickness. For example, the rollers 218 may compress the roofingmembrane 200 such that the second adhesive material 206 has a thicknessof less than about 4 mils, less than about 3.5 mils, less than about 3mils, less than about 2.5 mils, less than about 2 mils, less than about1.5 mils, less than about 1 mil, or less. The first adhesive material204 may have a thickness of between about 2 mils and 15 mils. In someembodiments, a release liner 208 may be applied to the second adhesivematerial 206 before and/or as the roofing membrane 200 is compressed.The pressure from rollers 218 may help adhere the release liner 208 tothe roofing membrane 200. The release liner 208 may include a UVblocking material in some embodiments.

In some embodiments, the first adhesive material 204 may be cooled priorto application of the second adhesive material 206. The first adhesivematerial 204 may be cooled to a temperature that is lower than theapplication temperature of the second adhesive material 206. Forexample, the first adhesive material 204 may be cooled to a temperatureof between about 70° F. and 90° F. prior to applying the second adhesivematerial 206. The first adhesive material 204 may be actively cooled,such as using fans and/or other airflow devices, and/or may be passivelycooled by exposure to air prior to applying the second adhesive material206.

Upon completion of the formation of the roofing membrane 200, theroofing membrane 200 may be cut to desired dimensions and/or be woundonto a roll 218 for subsequent storage and/or shipment. For example theroofing membrane 200 may be cut to a width of between about 24 inchesand 144 inches and a length that is specified by a customer and/orapplication. The final roofing membranes 200 may be installedimmediately after manufacture and/or stored for later use. If stored,the roofing membranes 200 may be maintained at temperatures of less thanabout 160° F., which may help prevent the adhesive materials fromoxidizing.

The methods, systems, and devices discussed above are examples. Someembodiments were described as processes depicted as flow diagrams orblock diagrams. Although each may describe the operations as asequential process, many of the operations can be performed in parallelor concurrently. In addition, the order of the operations may berearranged. A process may have additional steps not included in thefigure. It will be further appreciated that all testing methodsdescribed here may be based on the testing standards in use at the timeof filing or those developed after filing.

It should be noted that the systems and devices discussed above areintended merely to be examples. It must be stressed that variousembodiments may omit, substitute, or add various procedures orcomponents as appropriate. Also, features described with respect tocertain embodiments may be combined in various other embodiments.Different aspects and elements of the embodiments may be combined in asimilar manner. Also, it should be emphasized that technology evolvesand, thus, many of the elements are examples and should not beinterpreted to limit the scope of the invention.

Specific details are given in the description to provide a thoroughunderstanding of the embodiments. However, it will be understood by oneof ordinary skill in the art that the embodiments may be practicedwithout these specific details. For example, well-known structures andtechniques have been shown without unnecessary detail in order to avoidobscuring the embodiments. This description provides example embodimentsonly, and is not intended to limit the scope, applicability, orconfiguration of the invention. Rather, the preceding description of theembodiments will provide those skilled in the art with an enablingdescription for implementing embodiments of the invention. Variouschanges may be made in the function and arrangement of elements withoutdeparting from the spirit and scope of the invention.

Having described several embodiments, it will be recognized by those ofskill in the art that various modifications, alternative constructions,and equivalents may be used without departing from the spirit of theinvention. For example, the above elements may merely be a component ofa larger system, wherein other rules may take precedence over orotherwise modify the application of the invention. Also, a number ofsteps may be undertaken before, during, or after the above elements areconsidered. Accordingly, the above description should not be taken aslimiting the scope of the invention.

Also, the words “comprise”, “comprising”, “contains”, “containing”,“include”, “including”, and “includes”, when used in this specificationand in the following claims, are intended to specify the presence ofstated features, integers, components, or steps, but they do notpreclude the presence or addition of one or more other features,integers, components, steps, acts, or groups.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly or conventionally understood. As usedherein, the articles “a” and “an” refer to one or to more than one(i.e., to at least one) of the grammatical object of the article. By wayof example, “an element” means one element or more than one element.“About” and/or “approximately” as used herein when referring to ameasurable value such as an amount, a temporal duration, and the like,encompasses variations of ±20% or ±10%, ±5%, or +0.1% from the specifiedvalue, as such variations are appropriate to in the context of thesystems, devices, circuits, methods, and other implementations describedherein. “Substantially” as used herein when referring to a measurablevalue such as an amount, a temporal duration, a physical attribute (suchas frequency), and the like, also encompasses variations of ±20% or±10%, ±5%, or +0.1% from the specified value, as such variations areappropriate to in the context of the systems, devices, circuits,methods, and other implementations described herein.

As used herein, including in the claims, “and” as used in a list ofitems prefaced by “at least one of” or “one or more of” indicates thatany combination of the listed items may be used. For example, a list of“at least one of A, B, and C” includes any of the combinations A or B orC or AB or AC or BC and/or ABC (i.e., A and B and C). Furthermore, tothe extent more than one occurrence or use of the items A, B, or C ispossible, multiple uses of A, B, and/or C may form part of thecontemplated combinations. For example, a list of “at least one of A, B,and C” may also include AA, AAB, AAA, BB, etc.

What is claimed is:
 1. A method of manufacturing a self-adhering roofingmembrane, comprising: applying a first adhesive layer to a major surfaceof a polymeric roofing membrane; at least partially curing the firstadhesive layer; applying a UV curable adhesive layer atop the at leastpartially cured first adhesive layer; exposing the UV curable adhesiveto a UV light source to at least partially cure the UV curable adhesivelayer; and compressing the polymeric roofing membrane, the firstadhesive layer, and the UV curable adhesive layer to form aself-adhering roofing membrane, wherein after compression the UV curableadhesive layer has a thickness of less than about 4 mils.
 2. The methodof manufacturing a self-adhering roofing membrane of claim 1, wherein:applying the UV curable adhesive comprises one or more selected from agroup comprising roll coating, die coating, spray coating, and transfercoating.
 3. The method of manufacturing a self-adhering roofing membraneof claim 1, wherein: exposing the UV curable adhesive to the UV lightsource comprises exposing the UV curable adhesive to between about 100millijoules of energy per cm² and 300 millijoules of energy per cm². 4.The method of manufacturing a self-adhering roofing membrane of claim 1,wherein: the light source comprises a light source that emits light inone or more of a UVA wavelength, a UVB wavelength, and a UVC wavelength.5. The method of manufacturing a self-adhering roofing membrane of claim1, wherein: the light source comprises natural light.
 6. The method ofmanufacturing a self-adhering roofing membrane of claim 1, wherein: theat least partially cured first adhesive layer is at a lower temperaturethan the UV curable adhesive layer during application of the UV curableadhesive layer.
 7. The method of manufacturing a self-adhering roofingmembrane of claim 1, further comprising: applying a release liner to theUV curable adhesive layer before or during compression of the polymericroofing membrane, the first adhesive layer, and the UV curable adhesivelayer.